Panel: Corps did what it could to prevent Mo. River flooding, still changes needed

Gavins Point Dam in South Dakota releases 150,000 cubic feet per second of water June 14, 2011. Releases from the dam and others in the area were slowed to try to help with flooding of the Missouri River.

Hydrologist Bill Lawrence of the National Weather Service participated in the panel review and says Montana's record-breaking rainfall in May contributed to unprecedented runoff downstream.

But Lawrence also says severe wet spells - and droughts - are becoming more frequent.

"Whether or not you believe in climate change is besides the point," Lawrence said. "But we have the facts to prove that at least in the Missouri Basin the rainfall variability is becoming more extreme."

Lawrence says the Master Manual, which guides water management on the Missouri River, needs to be revised to allow the Corps to better respond to changing weather patterns.

The panel also recommended improving forecasting of snowmelt in plains states.

Panel member Neil Grigg of Colorado State University says the Corps has to balance flood control against the other Congressionally-authorized purposes for the Missouri River.

"Seven of those purposes require the reservoirs to store water for recreation or to release for navigation and other purposes," Grigg said. "And flood control is the other purpose, and it has sort of an opposite requirement that we want to leave the reservoirs partially empty to capture the flood runoff."

The panel has recommended a review of available flood storage to be completed by next spring.

Read the full report of the panel's findings released by the US Army Corps of Engineers here.